Pregate oxidation treatment using radio frequency activated nitrogen in a rapid thermal reactor

A rapid thermal treatment in nitrogen could be inserted immediately before the gate oxidation step in a typical process flow for making metal-oxide-se miconductor field effect transistors. The treatment, performed in a radio f requency induction heated single-wafer rapid thermal reactor, is used to re duce the subsequent oxidation rate and to incorporate nitrogen in the resul ting gate dielectrics. It is believed that activated molecular or atomic ni trogen is generated in the rapid thermal reactor and is responsible for the slight nitridation of the exposed silicon area during the rapid thermal tr eatment. Potential radiation damage to the silicon area is minimized by act ivating the nitrogen remotely from the wafer chamber. The effects of the ni trogen flow rate and the temperature during the treatment process on the ki netics of the subsequent oxidation in a regular furnace and the chemical co mposition of the resulting gate dielectrics are studied. Potential use of t he proposed treatment in making scaled devices is discussed. (C) 1999 The E lectrochemical Society. S0013-4651(97)10-080-5. All rights reserved.